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9
3
BASIC OPERATION
3
■
Receiving and transmitting
CAUTION:
Transmitting without an antenna will damage
the transceiver.
q
Push
[POWER]
to turn ON the transceiver.
w
Set the audio and squelch levels.
➥
Rotate
[SQL]
fully counterclockwise first.
➥
Rotate
[VOL]
to adjust the audio output level.
➥
Rotate
[SQL]
clockwise until the noise disappears.
e
While holding down
[H/L]
, push
[CH/WX]
several times to
change the channel group. (p. 8)
r
Rotate
[SELECTOR]
to select a channel.
(pp. 6, 7, 61)
• Pushing the keypad keys, or
[
Y
]
/
[
Z
]
on the microphone, also
selects a channel.
• When receiving a signal, “
BUSY
” is displayed and audio is
heard from the speaker.
• You may need to further adjust
[VOL]
.
t
Push
[
O
]
, then push
[6•
LO/DX
]
to turn the receive
Attenuator function ON or OFF, if necessary.
• “
LOC
” is displayed when the receive Attenuator is ON.
y
Push
[H/L]
to select the output power, if necessary.
• “
25W
” or “
1W
” is displayed when high or low power is selected.
• Choose low power for short range communications, choose
high power for longer distance communications.
• Some channels are restricted to only low power.
u
Hold down
[PTT]
to transmit, then speak into the
microphone at your normal voice level.
• “
TX
” is displayed.
• Channel 70 cannot be used for transmission other than DSC.
i
Release
[PTT]
to receive.
Simplex channels, 3, 21, 23, 61, 64, 81, 82 and 83
CANNOT
be lawfully used by the general public in USA waters.
IMPORTANT:
To maximize the readability of your
transmitted signal, pause a few seconds after pushing
[PTT]
, hold the microphone 5 to 10 cm (2 to 4 inches)
from your mouth and speak at a normal voice level.
VOL
iM604
VHF MARINE
MIC
U/I/C
9
16
SQL
DISTRESS
Microphone
w
e
e
t u i
q
r
r
y
e
y
r
✔
NOTE for Time-out Timer (TOT) function
The TOT function inhibits continuous transmission over a
preset period of time after the transmission starts.
10 seconds before the TOT function activates, a beep sounds
to indicate the transmission will be shut down and “
TOT
” is
displayed on the channel comment indicator. Transmission is
not possible for 10 seconds after this transmission shut down.